紫外光谱技术在超临界流体技术中的应用

在阐述超临界CO2萃取工艺原理的基础上,分别介绍了离线和在线紫外-可见光光谱技术在超临界流体技术中的应用情况,分析了在线紫外光谱技术的应用特点,指出了在线检测应用中所遇到的问题,同时对其前景进行了展望。     

超临界流体萃取技术的应用

介绍了超临界CO2萃取技术的优点及使用的改性剂,对超临界流体萃取技术在医药工业、食品工业、环境保护中的应用进行了详细阐述,指出应加快超临界流体萃取技术应用的产业化步伐。     

超临界萃取新技术在中药提取分离中的应用

本文论述了超临界萃取中药提取在中药产业化形势及应用新技术的意义,超临界CO2流体萃取新技术在中药提取分离中的应用及其优越性。同时阐述了超临界CO2流体萃取技术在中药提取分离及中药现代化中的应用方式及前景。     

超临界CO2萃取的研究进展

通过对各类超临界CO2流体萃取实验的文献报道和实验操作进行分析,对超临界CO2流体萃取技术的原理、特点和超临界CO2流体萃取的主要影响因素及其优化方法和经验模型进行了综述.     

超临界CO2萃取的研究进展

超临界CO2流体萃取技术是近年来兴起的一项具有精馏和萃取两过程的高新物质分离精制技术，文章主要通过对各类超临界CO2流体萃取实验的文献报道和实验操作进行分析，对超临界CO2流体革取技术的原理、特点和超临界CO2流体萃取的主要影响因素及其优化方法和经验模型进行了综述。     

超临界CO2流体萃取的应用进展

超临界CO2流体萃取技术已成为一种新兴分离技术,具有操作简单、快速、效率高、无毒、无污染等优点使其广泛应用于各个领域。文章主要介绍了超临界CO2流体萃取技术的原理及优点,综述了近年来超临界流体萃取技术在食品工业、天然香料工业及中草药开发中的应用,并进行了展望,指出了存在的问题和今后发展的趋势。     

超临界萃取技术及其应用

回顾了超临界流体（SCF）的研究历史,介绍了超临界流体的特性,分析了一元和三元体系的高压相图,简述了超临界流体萃取技术的原理、萃取过程和技术特点,并举例说明了CO2超临界流体在天然药物成分提取中的应用。     

超临界CO2络合萃取重金属研究进展

超临界流体萃取作为一种新型分离技术,不能直接萃取重金属等离子型物质,但能萃取离子与配合剂反应生成的配合物。将配合反应与超临界CO2流体萃取结合形成了又一门新型的萃取技术—超临界CO2络合萃取。在总结国内外文献的基础上,介绍了超临界CO2络合萃取重金属的原理、影响因素以及最新进展情况。     

超临界萃取-蒸馏耦合技术及在天然产物提取中的应用

简要介绍了超临界流体(SCF-CO2)萃取技术和分子蒸馏(MD)技术的性质和特点,综述了超临界CO2萃取与精馏、超临界CO2萃取与分子蒸馏两项联用技术,以及它们在天然产物提取中的应用,证明了该项耦合技术是先进的绿色操作工艺.     

超临界CO2流体萃取装置的污染分析与控制

针对超临界CO2流体萃取装置的工艺特点,分析了超临界CO2流体萃取装置中主要污染物的组成种类及其主要来源,指出噪声是超临界CO2流体萃取装置的主要污染物,同时提出从污染源着手,控制和减少超临界CO2流体萃取装置污染的一些措施.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.